Radiation and Tea in Japan

hello evrybody, unfortunately i don't have so much time to read and translate the other pages (newborn in house!), i have to place a new order, is it completely safe to buy tea from uji (ippodo, maiko, etc.) and kagoshima?

Hey I don't know if it was completely necessary but I made a combination of the two maps previously posted.. Also, I labeled the three regions that Chip said most commonly export green tea to the West. Lol I like making maps

I can't claim to "know" any sources, but O-cha was mentioned as one you like. So can one assume their Kagoshimas are legit and unblended?

It's heartbreaking.

This is EXACTLY why you need to ask querstions! Blending is common in Japan whose teas are quite suited to this technique. Blending when done properly and with purpose can be a good thing.

Therefore, asking direct questions, politely since Japanese are very polite people generally, will help to eliminate doubt. "Do any of your teas contain Shizuoka tea or any contain tea with raised radiation levels from the Fukushima nuclear accident?"

To directly answer your question ... O-Cha does have some blended teas, some are not, but none contain Shizuoka tea at this time. O-Cha also has some single estate teas that might even be blended within that one estate in order to create the best tea possible ... Kevin would be willing and able to answer these questions best.

As would any reputable vendor. I cannot emphasize enough about relationships with vendors, especially now more than ever. While it is best that this was occuring previously, you can begin now.

radiowonderland wrote:How 'bout a quarter of a pound? I have about 12 oz left, and it's been kept airtight and in the dark (and some of it in the freezer too.) Should I post over in the swap forum or would that be weird?

Should I throw out the lovely 1lb of Sencha I got from Den's Tea in October?

No.

To paraphrase myself: in order to get a CED (Committed Effective Dose) of radiation at a level known to be harmful (10 REM, no level lower than this has ever been proven to cause anything, and that's an acute dose, not a chronic dose, which is what you'd get from drinking tea, acute doses are more harmful than chronic ones), and using all sorts of conservative assumptions (such as 100% transfer of contamination to the tea liquor, 100% bodily absorption of contamination, 100% gamma ray absorption, and others, all of which are completely untrue, but estimated on the high side of dose, not the low side), you would have to consume literally (not figuratively) a tonne (that's 1000 Kilograms) of the worst contaminated tea found to date.

16 oz of potentially contaminated tea bears as much relationship to a tonne of contaminated tea as stubbing your toe does to falling out of orbit.

I'm doing my best not to beat a dead horse here, but please be careful about putting fallout from nuclear reactors in the same category as x-rays and "background radiation." Background radiation doesn't contain volatile isotopes of plutonium such as neptunium and americium; or xenon, strontium, and other byproducts of nuclear fission that are still being found in "hotspots" hundreds of miles away (and later blamed on archaic "Radon canisters" by TEPCO/Japan).

While its true that 100 rem (aka acute radiation syndrome) is the only way to see a 100% cancer causality rate from radiation, cancer has a curious way of following fallout 5-10 years down the road. Especially when they're just now detecting up to 1600millisievert/hr (160 REM/hr) on the floor of Reactor 3 -- the highest levels to date.

With all that said, I really do think that dilution works in our favor when it comes to tea -- you would have to EAT pounds of tea in order to absorb the ~300-500 bq of Cesium found in the most contaminated tea grown in Shizuoka. I'm not going to say that its 100% safe, but it's utterly harmless in comparison to the food that's being served in school lunches everyday in Fukushima.

It's really a shame that Shizuoka's tea has been effectively blacklisted, as this year's crop was some of the most delicious tea I've ever had the pleasure of tasting (particularly Den's Houryoku, Zuiko, and Maki). However, without firm radiation results, I really can't justify rolling the dice when there's Yame and Kagoshima sencha to be drunk!

Cole wrote:I'm doing my best not to beat a dead horse here, but please be careful about putting fallout from nuclear reactors in the same category as x-rays and "background radiation."

It's apparently not much of a dead horse since it keeps kicking. Background radiation like medical x-rays and such take the same form, and cause the same effects as fallout from nuclear reactors. Those are alpha, beta, gamma and neutron radiation. Muon and proton radiation aren't present in nuclear fallout, but have similar effects to beta and alpha radiation, respectively.

Cole wrote:Background radiation doesn't contain volatile isotopes of plutonium such as neptunium and americium; or xenon, strontium, and other byproducts of nuclear fission that are still being found in "hotspots" hundreds of miles away (and later blamed on archaic "Radon canisters" by TEPCO/Japan).

Plutonium, neptunium, and americium aren't volatile, and won't be present unless they are physically ejected from nuclear material (as happened in Chernobyl as well as the dozens of atmospheric nuclear tests). All of these are present in minute, but detectable, quantities around the world as fallout from atmospheric nuclear tests, and no reliable reports have shown elevated levels of these elements in Japan after the Fukushima disaster.

Plutonium (and other Transuranic isotopes and decay products) are primarily alpha emitters. The primary source of natural background radiation exposure is radon, which is an alpha emitter (radon is present all over as a decay product of natural uranium 238). All alpha radiation is pretty much the same, it is extremely damaging to tissue but unable to penetrate deeply. Alpha radiation from transuranic metals tends to cause leukemia, as the transuranic metals are bio-accumulated in bone tissue. Alpha radiation from radon tends to cause lung cancer, as radon doesn't bio-accumulate in the body.

The primary fallout from a nuclear disaster consists of strontium-90 and caesium-137. Neither a volatile, they are present in large amounts (radioactively speaking) because they are the decay products of krypton-90 and xenon-137, which, as noble gases are volatile and escape from the fuel cladding easily. Cesium-137 is a beta-gamma emitter and strontium-90 is a beta emitter. Both have radiation spectra similar to naturally occurring isotopes such as potassium-40 (which is a major component of the natural background radiation your are normally exposed to).

Cole wrote:While its true that 100 rem (aka acute radiation syndrome) is the only way to see a 100% cancer causality rate from radiation, cancer has a curious way of following fallout 5-10 years down the road. Especially when they're just now detecting up to 1600millisievert/hr (160 REM/hr) on the floor of Reactor 3 -- the highest levels to date.

An acute (not chronic) radiation dose of 100 REM will often cause radiation sickness, but only extremely rarely results in death. It will only result in slightly increased cancer rates long term, not 100% casualty rates. Chronic radiation doses are less dangerous than acute doses because the body's repair mechanisms have more time to work in between damage events in chronic doses. People in places with high background radiation, such as Ramsar, Iran (where the yearly dose is 250 mSv), typically do not experience elevated rates of cancer.

They are detecting radiation rates of 1600 mSv/hr (maximum, not everywhere) inside the reactor containment buildings, where nobody is going (because they are detecting those high radiation rates), not on tea (which is why they build big, expensive reactor containment buildings). Cleaning up Fukushima Daiichi is going to be an expensive, dangerous mess (hey, don't put your backup generators below the level where they'll be swamped by a tsunami). It's not an expensive, dangerous mess that's present in your tea.

And since you accused me of being careless in talking about radiation, I'm a Physicist working for the US Dept. of Energy in radioactive cleanup (and any opinions presented are solely mine, and not those of the Dept. of Energy).